Jasch industries offers an on-line thickness gauging and control system, [btg 3000]. It provides precise on-line thickness and basis weight measurement of flat sheet products. The system uses nuclear sensors for non-contacting measurement. The measuring head consists of a nuclear source and a high sensitivity ion chamber radiation detector. Radiation from the source is absorbed by the moving product in precise proportion of its basis weight. The resultant signal from the detector is amplified and linearized with reference to the calibration curve and displayed on the control console. The measuring head uses a temperature stabilised amplifier and air gap temperature sensors to compensate for the effect of ambient temperature variations. The system also periodically carries out an autocalibration process to maintain measurement accuracy. It includes a precision manufactured o-frame scanner free from deflection and misalignment to ensure precise sensor positioning. The frame is totally enclosed from all sides to shield all mechanical and electronic components. Maximum use is made of standard parts to cut down initial investment and maintenance costs. The operation is supervised and controlled by a pc based system linked to the scanner and measuring head through a rs-485 serial link. The display unit features touch-screen controls which offer an ease of understanding and use. Standard displays include cross web and machine direction profiles along with trends and history pages. The process parameter are set from pre-stored product recipe or selected by the operator. Customised roll reports with print out at predefined intervals or upon demand can be generated.
